Holding tool



Nov. 15, 1966 A. c. HOTT ETAL.

HOLDING TOOL Filed Nov. 15, 1963 m T m V m ALBERT C. HOTT VINTON C. DAVIS United States Patent Ofiice 3,234,962 Patented Nov. 15, 1966 3,284,962 HOLDING TOOL Albert C. Hott, Northridge, and Vinton C. Davis, Van Nuys, Calif., assignors to North American Aviation,

Inc.

Filed Nov. 15, 1963, Ser. No. 324,095 2 Claims. (Cl. 51-217) The present invention relates to a holding tool and more particularly to a thin sectioning tool.

The technical and scientific proficiency of a materials laboratory is a measure of its capability for microscopic examination. Micorscopic examination to be both rapid and precise requires properly dimensioned specimens. For this reason, the rate of microscopic examination depends upon the ability of the laboratory to produce thin specimen sections.

Thin specimen sections are formed by securing a specimen chip to a commercially available glass slide and grinding the specimen in successive stages to the desired thickness. Small holders are used for the glass slides during the coarse and fine grinding stages. These holders are designed to retain several slides for the coarse grinding stages. However, the final grinding stage has been limited in the known art to a single slide because commercial glass slides Vary considerably in thickness. While the fine grinding of a single specimen produces the desired thin section for microscopic examination, it substantially reduces the total production of thin specimen sections in the laboratory, and this directly affects the laboratory proficiency.

Accordingly, it is an object of the invention to provide a new and improved holding tool for thin sectioning.

Another object of the invention is to provide a thin sectioning tool for grinding slide mounted specimens to fine tolerances.

A further object is to provide a tool which compensates for the varying thicknesses of glass slides.

Further objects, features and the attending advantages of the invention will be apparent with regard to the following description read in connection with the accompanying drawings in which:

FIGURE 1 is a perspective view, partly broken away, of the thin sectioning tool of the invention in an operating position;

FIGURE 2 is a transverse cross section, partially shown, of the tool shown by FIGURE 1; and

FIGURE 3 is an enlarged longitudinal cross section, partially shown, of the tool shown by FIGURE 1.

Briefly, in accordance with the invention, a new and improved holding tool for thin sectioning is provided which assists in grinding one or more slide mounted specimens to fine tolerances by compensating for the varying thicknesses of the slides. The tool comprises springloaded first and second members, and an associated clamp means adapted to bear upon the specimen slides and retain the slides for thin sectioning.

Referring now to FIGURE 1, one embodiment of the thin sectioning tool of our invention is shown positioned on a level magnetic chuck 12. Magnetic chuck 12 is similar to those used with well-known precision surface grinders. The chuck 12 can exhibit longitudinal travel, transverse travel, and vertical travel; all with respect to a conventional grinding wheel or the like, such as diamond impregnated wheel 14.

The thin sectioning tool 10 has opposed rectangular bars 16 and 18 which are suitably formed from a non-magnetic material such as aluminum and the like. The bars 16 and 18 are preferably connected by one or more fastening members, such as stripper bolts 20 and 22. The

bolts 20 and 22 extend through respective apertures 24 and 26 in bar 18, and threadably engage bar 16.

Bars 16 and 18 are urged into the spaced-apart relationship shown by FIGURE 1 by suitable spring means. In the tool 10 as shown, compression springs 28 and 30 are positioned on the respective bolts 20 and 22 between bars 16 and 18. The springs 28 and 30 resist clamping forces applied to the bars 16 and 18, and tend to urge the bars to a maximum, spaced-apart relationship; the latter being limited by the bolts 20 and 22.

A shell member 36 associated with the bars 16 and 18 can be assembled from side rails 38 and 40 which are secured to similar end plates 42 by removable fastening means, such as similar screws 46. The side rails 38 and 40 are preferably formed from a magnetic material such as steel and the like. It is contemplated that the assembled shell member 36 can be formed from magnetic material. Shell member 36 can be suitably formed as a singular member; however, it is desirable to assemble the shell member as shown by FIGURE 1 since this construction facilitates positioning the member around the connected bars 16 and 18.

The side rails 38 and 40 have inwardly extending flange portons 48 and 50, respectively. Flange portions 48 and 50 can be integrally formed with the respective side rails as shown or separate members connected to the side rails. The flange 50 of side rail 40 is more clearly shown by FIGURE 2. Flanges 48 and 50 are carefully machined so that the distances from the base of shell member 36, i.e. the surface nearest the magnetic chuck 12, to the clamping surface 54 of each flange are dimensionally matched.

A resilient material such as rubber and the like is positioned on, and preferably secured to, the exposed surface of bar 16. This resilient material, as shown by FIGURE 1, can be longitudinally and transversely spaced-apart resilient pads 56. A singular pad of resilient material or several strips of resilient material can also be used, although the multiple pads 56 are preferred.

Operatively, the shell member 36 is removed from its normal position around the spring-loaded and spacedapart bars 16 and 18. Commercial glass slides 60 are positioned on the resilient pads 56 as shown by FIG- URE 1. Each glass slide 60 has a specimen 62 suitably secured thereto in a well-known manner. Shell member 36 is then positioned around the bars 16 and 18 so that the clamping surface 54 of each flange 48 and 50 rests upon the associated ends of the glass slides 60 (see FIG- URE 2).

The weight of the shell member 36 bears upon the glass slides 60 and partially depresses the resilient material of the pads 56. However, the spring means associated with the bars 16 and 18, e.g. compression springs 28 and 30, resist this compressive load and maintain the base of the shell member 36 in an adjacent to but spaced apart relationship with respect to the magnetic chuck 12.

When the magnetic chuck 12 is energized in a conventional manner, the resistance of the spring means is overcome and the base of the shell member bears upon the surface of the chuck. Since the flanges 48 and 50 are dimensionally matched, each glass slide 60 is also forced toward the magnetic chuck 12. The slides 60 compress the resilient material of the pads 56 so that the specimen surfaces of each glass slide 60 are in a common plane.

The varying thicknesses of commercial glass slides are compensated by the thin sectioning tool 10 as more clearly shown by FIGURE 3. For example, the respective ends of a relatively thin glass slide 60A and a relatively thick glass slide 66B are pressed a proportionate distance into the associated resilient pads 56 by the side rail flange 40 when the magnetic chuck is energized. This orients the glass slides 60A and 603 so that the specimens 62 have a common base plane, i.e. the plane defined by the specimen surfaces of each glass slide.

Grinding multiple specimens to a uniform thickness can thus be easily accomplished with an increased degree of accuracy by use of the thin sectioning tool.

As Will be evidenced from the foregoing description,-

certain aspects of the invention are not limited to the particular details of construction illustrated, and it is contemplated that other modifications and applications will occur to those skilled in the art. It is, therefore, intended that the appended claims shall cover such modifications and applications that do not depart from the true spirit and scope of the invention.

Having described the invention, what is claimed is:

1. A holding tool for thin sectioning comprising:

(a) first and second movable members having opposed surfaces in a spaced-apart relationship,

(b) connector means joining said first and second members and limiting the spaced-apart relationship of said first and second members,

(0) spring means associated with said first and second members,

(d) said spring means moving at least one of said first and second members with respect to the other,

(e) resilient means carried by an exposed surface of said first member to receive at least one specimen slide,

(f) a movable shell member generally surrounding said first and second members,

(g) said shell member suitably formed from a magnetic material, and

(h) clamp means associated with said shell member to bear upon the specimen slide so that a magnetic means cooperating with the holding tool attracts said shell member and said clamp means to subthe slide and said resilient means.

2. A thin sectioning tool for holding specimen slides comprising:

(a) first and second movable members having opposed surfaces in a spaced-apart relationship,

(b) at least one of said movable members formed from a nonmagnetic material,

(c) connector means joining said first and second members and limiting the spaced-apart relationship of said first and second members,

(d) compression spring means associated with said connector means and urging said first and second members into the spaced-apart relationship,

(e) resilient means carried by an exposed surface of said first member to receive at least one specimen slide,

(f) a shell member generally surrounding said spacedapart first and second members,

g) said shell member including opposed side rail members suitably formed from a magnetic material so that a magnetic means cooperating With the thin sectioning tool attracts said side rail members, and

(h) inwardly extending flange portions associated with said side rail members and dimensionally matched to bear upon the specimen slides and substantially overcome said spring means so that the slides are depressed into said resilient means and further depressed and retained by the attraction of the magnetic means on said shell member with the exposed slide surfaces in a common plane defined by said matched flange portions.

I References Cited by the Examiner UNITED STATES PATENTS 2,111,299 3/1938 Robbins 2698 3,089,296 5/1963 Brady I 51-277 FOREIGN PATENTS 431,319 7/1935 Great Britain.

HAROLD D. WHITEHEAD, Primary Examiner. 

1. A HOLDING TOOL FOR THIN SECTIONING COMPRISING: (A) FIRST AND SECOND MOVABLE MEMBERS HAVING OPPOSED SURFACES IN A SPACED-APART RELATIONSHIP, (B) CONNECTOR MEANS JOINING SAID FIRST AND SECOND MEMBERS AND LIMITING THE SPACED-APART RELATIONSHIP OF SAID FIRST AND SECOND MEMBERS, (C) SPRING MEANS ASSOCIATED WITH SAID FIRST AND SECOND MEMBERS, (D) SAID SPRING MEANS MOVING AT LEAST ONE OF SAID FIRST AND SECOND MEMBERS WITH RESPECT TO THE OTHER, (E) RESILIENT MEANS CARRIED BY AN EXPOSED SURFACE OF SAID FIRST MEMBER TO RECEIVE AT LEAST ONE SPECIMEN SLIDE, (F) A MOVABLE SHELL MEMBER GENERALLY SURROUNDING SAID FIRST AND SECOND MEMBERS, (G) SAID SHELL MEMBER SUITABLY FORMED FROM A MAGNETIC MATERIAL, AND (H) CLAMP MEANS ASSOCIATED WITH SAID SHELL MEMBER TO BEAR UPON THE SPECIMEN SLIDE SO THAT A MAGNETIC MEANS COOPERATING WITH THE HOLDING TOOL ATTRACTS SAID SHELL MEMBER AND SAID CLAMP MEANS TO SUBSTANTIALLY OVERCOME SPRING MEANS AND DEPRESS THE SLIDE AND SAID RESILIENT MEANS. 